Solid propellant rocket motors employ a propellant comprising a solid fuel charge or “grain” which burns to generate exhaust gases and other combustion products, which are expelled through one or more nozzles of the rocket motor to provide thrust. Once a grain of solid propellant is ignited, it is difficult to extinguish and the entire grain is ordinarily consumed after ignition. Additionally, effecting variation of thrust is more difficult in solid propellant than in liquid propellant rocket engines. However, simple structural design of solid propellant rocket motors and ease of storage of the solid propellant are advantages of the solid propellant motor.
Methods of controlling the thrust of a solid propellant motor often involve complicated control schemes, which may require extensive computing power and/or multiple controllers so that the rocket may operate over a wide range of operating conditions.
In view of the foregoing, it would be desirable to have control systems and methods to control the thrust of a solid propellant rocket motor that utilize relatively easily acquired system data, such as pressure, and compensate for unknown variables. Additionally, it would be desirable if the control systems and methods required relatively little computing power and utilized a controller that is operable over a relatively large range of operating conditions, such as over a relatively large range of pressures. Furthermore, it would be desirable to simulate and evaluate rocket designs utilizing control methods that require relatively little computing power.